Chicago Police use Excessive Force, DOJ finds

(CNN)The Chicago Police Department has unconstitutionally engaged in a pattern of excessive force, US Attorney General Loretta Lynch said Friday, wrapping up a 13-month federal probe of a department that was under heavy scrutiny over officer-involved shootings.

As a result of the probe, the city and the Justice Department, which began investigating the CPD in December 2015, have agreed to negotiate a reform plan that would be overseen by a federal judge, Lynch said in Chicago.

Chicago police officers' use of excessive force, she said, stemmed in large part from what the Justice Department found was severely insufficient training and accountability procedures.

Friday's announcement comes more than two years after the fatal shooting by Chicago police of 17-year-old Laquan McDonald, a case that spurred reforms and protests and helped fuel a national conversation about police officers' use of deadly force.